Book/Report

FZJ-2019-05088

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Entwicklungen zur Spurenanalytik in Mikrovolumina und deren Anwendung bei der Charakterisierung von Niederschlagsereignissen und einzelnen Regentropfen

Baade, A. (Corresponding author)FZJ*

1999
Forschungszentrum Jülich, Zentralbibliothek, Verlag Jülich

Please use a persistent id in citations: http://hdl.handle.net/2128/23110

Report No.: Juel-3709

Abstract: Rain is the predominant route for the atmospheric deposition of environmentally relevant compounds. For a better understanding of wash-out effects of metals such as Pb, Cu, and Cd it is necessary to examine individual rain events. The main focus of the present work was the determination of trace heavy metals in individual rain drops and rain drop fractions for a detailed investigation of different precipitation events such as cloudburst, drizzle, hail and snow. Moreover, the wash-out rate during the first minutes of rain events and the comparison of a typical urban location (Essen) with a rural area (Jülich) were of special interest. The method development included a sampling procedure for individual and size-classified rain drops by using liquid nitrogen. Furthermore, an approach for the determination of trace heavy metals in microvolumes was introduced. The measurements have been performed by using voltanunetric techniques based on microelectrodes and ETV-ICP-MS. The possibilities and limitations of these approaches are shown. The stripping voltammetry required the development of specially designed measuring cells and single microelectrodes or microelectrode arrays. By such procedures determinations of Pb, Cu, Cd and Zn were carried out in microliters of rain water (2-100 $\mu$l) and absolute detection limits in the lower picogram range were achieved. Additionally a thin-layer flow cell in combination with microelectrode arrays was developed and the influence of a piezo actuator on the accumulation efficiency of the analyte on the electrode surface was discussed. By the application of these analytical methods on precipitation samples, specific concentration maxima in defined drop size fractions were found for Pb, Cu and Cd at both sampling sites (Essen, Jülich). For lead an increase of themetal concentration in drop volumes of 4 and 8 $\mu$l was detected. All rain events showed a strong decrease in metal concentrations after 3 to 10 minutes. In addition to metal determinations the pH in rain drop fractions was analysed with ion-sensitive field effect transistors (ISFET). Also the Input of major rain water constituents at both sampling areas was characterized by using ion chromatography and ETV-ICP-MS. Generally large concentration variations of all measured compounds between weekly collected rain samples were observed, but the average concentrations over the year were similar at both sampling areas. Obviously, the influence from local emission sources was low.

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Contributing Institute(s):

1. Publikationen vor 2000 (PRE-2000 ; Retrocat)

Research Program(s):

1. 899 - ohne Topic (POF3-899) (POF3-899)

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Database coverage:

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